Intel Xeon E5640 's Advantages
Higher base frequency (2.666GHz vs 2.1GHz)
Lower TDP (80W vs 140W)
Intel Xeon E7 8870 v3 's Advantages
Released 5 years and 3 months late
Higher specification of memory (DDR3 vs DDR3)
Newer PCIe version (3 vs 2)
Larger L3 cache size (45MB vs 12MB)
More modern manufacturing process (22nm vs 32nm)